Headunit help

MURRAYS444

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Hi

I put an aftermarket headunit in my car and the rear speakers are not working I bought the a autoleads connecter and still nothing from the rear speakers.
The car in question is an audi s4 b5 saloon 2000 plate.
Here is a few pictures of the wiring






I have all the connectors plugged in apart from the red one which I think is for the rear speakers does anyone know the correct connector to get the rear speakers working
Thanks
 
Did you connect the blue/white wire to your headunit? It is a remote wire to switch on the amp when you turn the unit on.
 
Yeah connected the blue/white wire everything works apart from the rear speakers:huh:
 
The red connector with the blur and white should plug in but that maybe the rear amp lead try connecting to your head unit remote lead
 
Where did you connect the blue-white too?

Have you confirmed blue white is live with the radio on?

Thats also the wrong lead, the proper one connects to the pre-outs on the head unit, not the rear speaker channels.
 
Yeah. You should have a set of rca's coming out from the wiring you bought if your rears are amplified.
 
The answer is above, but I had a similar issue until I realised the blue/white rear amp remote wire has to be connected to a switched 12v supply, to receive the signal to power up the rear speakers.

Your new head unit should have a separate wire, often blue, labelled 'remote' or 'ant' that will supply the signal required. Note that 'ant' wires are primarily intended for aerial amplifiers, which you may need if radio reception is poor, so the head unit may only supply power to this wire while using the radio. You may get lucky and it stays on when the CD etc are used. If not, you need to find a switched live to use and preferably run a new one from the fuse panel itself, to avoid overloading an existing circuit.

One final point, check that all black wires in the line out converter adapter you used actually have a corresponding black/earth connection on your original Audi loom. If not, your rear speakers still won't work even if the blue/white wire is correctly connected.

Noticed others mention RCAs, your AUDI loom doesn't have them judging by the pictures.
 
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The RCA's are on the head unit, not the Audi loom.

His adaptor is taking the speaker output from the headunit, and feeding it into the line input of the rear amplifier. This is horrific.

The correct adaptor takes the correct line level pre-outs from the back of the head unit (using RCA jacks), and feeds them to the rear amplifier.
 
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The rear speaker outputs are fed through line out conversion circuitry in the black shrink wrap. Is this really horrific? Provided his head unit has rear preout RCAs this would be preferable so long as the head unit fader works with a mix of front speaker outs and rear RCAs
 
Ok I got the rear speakers working as I had connected the blue/white wire to the wrong one only have one more problem is that everytime I switch the car off the headunit resets its self and reverts back to the factory settings im sure theres a way for the headunit to have a memory of some sort
 
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on the loom for the new head unit the red wire and usually the yellow wire should have inline bullet connectors.

If they have swap them over as one is constant live ( for memory) and the other is ACC live which only powers up when ignition is on
 
Yeah I thought that might be it i'll have a look and see if I can sort it out let you know how I get on!
 
Yus sorted the memory problem too it was doing my head in when I was having to set it up every time I drove the car! Gonna try and fit a sub next :beerchug:

Thanks for all the helpful comments :salute:
 
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